Question

I was answering the questions in the lab guide when I noticed something about the bag. When I looked at it carefully, parts of it were turning purple. I lifted the bag out of the beaker and could see that the beaker was still the same color orange as when we started, but the white cornstarch solution was purple. It was amazing, and I knew exactly what had happened!

In the described experiment, explain what happened using the following words in your explanation: indicator, concentration, semipermeable, and diffusion.
A) The indicator turned orange, indicating a high concentration of cornstarch.
B) The semipermeable bag allowed diffusion of purple solution into the beaker.
C) The experiment started with purple solution and turned it into orange.
D) The concentration of the white cornstarch solution decreased over time.

Answer 1

In the experiment, the purple color change of the cornstarch solution inside the semipermeable bag indicated diffusion of the iodine as it reacted with the cornstarch, showing how substances can move through the barrier due to a concentration gradient.

Step-by-step explanation:

In the described experiment, the indicator, which was possibly iodine, reacted with the cornstarch in the bag. When the white cornstarch solution inside the semipermeable dialysis bag turned purple, it indicated that the cornstarch and indicator had reacted, demonstrating the occurrence of diffusion through the semipermeable membrane. The semipermeable nature of the bag allows certain molecules to pass through while blocking others, which explains why only parts of the bag turned purple. The purple areas suggest where diffusion of the indicator occurred due to its concentration gradient.